Yarn and other types of fibers used in the textile industry for carpeting and the like may be produced in part within a heat setting machine. Heat setting is a thermal process that gives yarn and other types of fibers dimensional stability, diminished torque, higher volume, wrinkle resistance, temperature resistance, and other desired properties. Due to the varying speeds of the several components within a typical heat setting line, an intermediate yarn accumulator may be used therein. For example, yarn may be pulled from a heat setting tunnel and fed onto the yarn accumulator in the form of a yarn sausage, i.e., an expanding or contracting mass of yarn in any form. In turn, a winder later pulls the yarn from the accumulator and winds the yarn onto bobbins and the like. The heat setting tunnel may operate in a substantially continuously fashion while the winder may operate intermittently so as to change bobbins as needed.
A rolling sled within the accumulator may compress the yarn sausage as it is being formed. The sled generally is weighted so as to make the yarn run efficiently towards the winder. The amount of weight generally is determined when the yarn sausage is first formed. The length of the yarn sausage, however, will vary during operation. If the pressure applied to the yarn sausage is not varied accordingly, the yarn may be pulled out of the accumulator in an uneven manner and thus may cause low efficiency at the winder. Although various types of sled tensioning devices are known, these devices generally use various types of electronics and other types of complex controls.
There is a desire therefore for a simplified but efficient tensioning device for a yarn accumulator so as to apply the appropriate tension to a yarn sausage during all stages of operation. Such a tensioning device may provide variable tension on the yarn sausage for high efficiency in feeding the yarn to a winder. Other types of linear fed devices also may be used herein.